Babysitter Parser Generator

Expert skill for parser generation and implementation using LL, LR, LALR, PEG, and Pratt parsing techniques

install

source · Clone the upstream repo

git clone https://github.com/a5c-ai/babysitter

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/a5c-ai/babysitter "$T" && mkdir -p ~/.claude/skills && cp -r "$T/library/specializations/programming-languages/skills/parser-generator" ~/.claude/skills/a5c-ai-babysitter-parser-generator && rm -rf "$T"

manifest: library/specializations/programming-languages/skills/parser-generator/SKILL.md

Parser Generator Skill

Overview

Expert skill for parser generation and implementation using LL, LR, LALR, PEG, and Pratt parsing techniques.

Capabilities

Generate parsers from grammar specifications (ANTLR, Bison, tree-sitter)
Implement recursive descent parsers with predictive parsing
Implement Pratt parsers for expression handling
Generate LALR/GLR parse tables
Implement PEG parsers with packrat memoization
Handle grammar conflicts (shift-reduce, reduce-reduce)
Generate concrete syntax trees (CST) and AST transformations
Implement operator precedence parsing

Target Processes

parser-development.js
language-grammar-design.js
ast-design.js
lsp-server-implementation.js

Dependencies

ANTLR4
tree-sitter
Bison/Yacc

Usage Guidelines

Grammar Analysis: Analyze grammar class requirements (LL(k), LALR, etc.) before selecting parser type
Conflict Resolution: Document and resolve all shift-reduce/reduce-reduce conflicts explicitly
Error Recovery: Implement synchronization points for robust error recovery
AST Construction: Design AST node types before implementing production actions
Expression Parsing: Use Pratt parsing for complex expression precedence handling

Output Schema

{
  "type": "object",
  "properties": {
    "parserType": {
      "type": "string",
      "enum": ["recursive-descent", "pratt", "lalr", "glr", "peg", "ll"]
    },
    "grammarClass": { "type": "string" },
    "conflicts": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "type": { "type": "string" },
          "resolution": { "type": "string" }
        }
      }
    },
    "generatedFiles": {
      "type": "array",
      "items": { "type": "string" }
    }
  }
}